> The CAFE achieved by a given fleet of vehicles in a given model year is the production-weighted harmonic mean fuel economy, expressed in miles per U.S. gallon (mpg), of a manufacturer's fleet of current model year passenger cars or light trucks with a gross vehicle weight rating (GVWR) of 8,500 pounds (3,856 kg) or less (but also including medium-duty passenger vehicles—such as large sport-utility vehicles and passenger vans—with GVWR up to 10,000 pounds), produced for sale in the United States. "
(Bonus points for the stupidity of using "harmonic mean of mpg" instead of a simple "gpm")
Also, CA has to work around Federal pre-emption
> Through EPCA and EISA, U.S. law (49 U.S. Code § 32919) also requires that "a State ... may not adopt or enforce a law or regulation related to fuel economy standards or average fuel economy standards".
Do you have evidence for this? I seem to recall that low-mpg light trucks and SUVs were wildly popular in the US until the price of gasoline went to $4.
Is that due to CAFE or due to consumer preference for fuel-efficient cars within a class? Since MPGS are heavily touted in advertising, it seems to be related to consumer preference
I'd credit most of that improvement on electronic engine control, and that really kind of had to evolve somewhat after 1980. You could see good improvement in cars from that time frame just by replacing the coil system with an SCR based ignition.
It's also difficult to explain how brittle a 1980 car's fuel handling system was. Now, having both controlled by the same computer leads to much improvement.
Alternative narrative: Customer demand shifted to cars with higher mileage. Auto makers stopped resisting higher CAFE standards because the minor increment was meaningless. See also: The ongoing debate over minimum wage laws and unemployment.
Inferring causation from correlation is not "pretty simple", but a lot of poor decisions are made under that assumption.
I can tell you for a fact that at least on large diesel truck forums when gas/diesel hit $4/gallon the number of used trucks being posted for sale was staggering. The number of people who couldn't afford to fill their trucks up and still make a payment was almost comical.
> https://en.wikipedia.org/wiki/Corporate_Average_Fuel_Economy...
https://en.wikipedia.org/wiki/Corporate_Average_Fuel_Economy
> The CAFE achieved by a given fleet of vehicles in a given model year is the production-weighted harmonic mean fuel economy, expressed in miles per U.S. gallon (mpg), of a manufacturer's fleet of current model year passenger cars or light trucks with a gross vehicle weight rating (GVWR) of 8,500 pounds (3,856 kg) or less (but also including medium-duty passenger vehicles—such as large sport-utility vehicles and passenger vans—with GVWR up to 10,000 pounds), produced for sale in the United States. "
(Bonus points for the stupidity of using "harmonic mean of mpg" instead of a simple "gpm")
Also, CA has to work around Federal pre-emption
> Through EPCA and EISA, U.S. law (49 U.S. Code § 32919) also requires that "a State ... may not adopt or enforce a law or regulation related to fuel economy standards or average fuel economy standards".